I knocked my MacBook a little and the screen suddenly went like this: Click for large view - Uploaded with Skitch not sure quite how to describe it to find out if anyone else has had this problem. I held the button down to power off and then turned it on again, which worked fine until I moved the MacBook slightly, and the same thing happened but its powered on again fine (if maybe slightly slower). I installed Lion when it came out but I've not had any other problems. I also replaced some ram about a month ago. Can anyone help tell me whats wrong?